Automatic control for oil pumps and the like



Oct. 27, 1936. H. J. HAMMERLY 2,059,102

AUTOMATIC CONTROL FOR OIL PUMPS AND THE LIKE Filed Nov. 17, 1934 2 Sheets-Sheet 1 .w n 33 H a /1o 25 16 f I 29 -'2 12 K 17;; l

I 42 41 1NvENT0R 45 46 HERMAN J..

AMME'R LY,

Oct. 27, 1936. J HAMMERLY 2,059,102

AUTOMATIC CONTROL FOR OIL PUMPS AND THE LIKE Filed Nov. 1'7, 1934 2 Sheets-Sheet 2 lNVENTOR Henna/w J. HAMMERLY,

Patented Oct. 27, 1936 UNITED STATES PATENT OFFICE 2.059.102 AUTOMATIC coN'raoL-ron on. PUMPS arm mm mm of Connecticut Application November 17, 1934, Serial No. 753,455

3 Claim.

This invention relates particularly to a float and thermostatically operated switch unit and this case is a partial continuation of application Serial Number 705,541 filed by me January 6,

1934 entitled Fuel oil supply.

The main object is to provide a control unit for an oil pump, the unit being of such character and construction that it may be readily installed in a pump casing and removed as a unit when 10 desired for the purpose of repair and replacement.

The construction in general embodies a casing containing an electric motor for driving a pump piston which is attached to the unit and isinsertable and removable therewith into the in fuel supply reservoir which itself furnishes the pump cylinder.

In addition to the motor and pump piston the unit includes a switch for controlling the motor circuit, this switch being thermostatically actu- 20 ated under certain conditions and also furnished with a float for actuating the switch under certain conditions, this float being also attached to and insertable and removable with the unit into the fuel supply reservoir or receptacle.

This unit also includes for convenience in manufacture and installation an extension cord or cable connection so'that in case anything goes wrong with the pump piston or the motor or switch or the float, these parts may be all re- 0 moved as a unit together with the electric connecting device and replaced with a new unit with a minimum interruption of service.

Fig. 1 is a vertical sectional view showing the principal parts of a construction embodying my invention.

Fig. 2 is a plan view showing the parts with the cover of the receptacle removed.

Fig. 3 is a horizontal sectional view of the switch unit.

40 Fig. 4 is a vertical sectional view of the switch unit.

Fig. 5 is a transverse sectional view of the switch unit.

Fig. 6 is an exploded perspective view showing 45 the fuel receptacle and the detachable parts embodying my present invention as claimed herein.

This construction is intended to replace the gravity feed bottle and reservoir commonly employed with oil burner stoves using kerosene or 50 fuel oil. The receptacle III has the main chamber l2, the constant level chamber II and the overflow'chamber l3.

The pump has a cylinder it which may be formed integral with or separately and attached as to the main body of the reservoir and in the bottom of which is a check valve l5 controlling the inlet. The piston l6 also has a check valve ll. The electric motor III which drives the pump maybe of any suitable type and is supported in a casing l9 which is detachably se- 5 cured in the receptacle ill in any suitable manner as for instance by means of one or more screws 20. The shaft 2| of the motor has a worm (not shown) meshing with worm gear 22 in the casing. This gear is on a shaft 23 which projects outside the casing l3 and has a crank arm 24 connected to the piston It by a connecting rod 25.

Liquid is drawn into the main chamber l2 by the action of the pump and flows through the passage 26 into the constant level chamber H. The flow through this passage is controlled by a needle valve 21 which in turn is regulated by a float 28. This float is pivoted at 23 so that as the float rises and falls it closes and opens the passage 26.

A filter pad 30 is preferably provided so as to remove foreign particles from the liquid which passes through from chamber l2 to chamber II. This filter pad is preferably removable for convenience in renewal, etc. Liquid normally flows from the chamber ll through outlet 3| to the burner or other point of consumption. The chamber l3 has an outlet 32 from which the overflow from the chamber I2 may pass back to the source of supply (not shown).

Electric current is supplied to the motor through a cable 33 which contains the necessary conductors and which is positioned by a bushing 34 removably seated in a notch in the edge of 35 the casing l9 and the notch 35 in the edge of the main reservoir. This bushing is held in place by the cover 38 of the receptacle.

The starting and stopping of the motor is controlled by a switch enclosed in a housing 40 made up of an insulating base 31 and a metal cover 38. This switch consists of the thermostatic arm 40 having one end looped around and secured to a support H and provided with an adjusting screw 42. The movable end of the arm carries a finger 43 which is hinged at 44 to the movable end of the arm. This finger carries a contact 45 which is adapted to snap back and forth between the abutment l6 and the stationary contact 41, a spring 48 being provided 50 for this purpose.

This switch is actuated by the thermostatic action commonly relied upon in switches of this character. The switch is also adapted to be actuated by a float 50 which is supported on the 66 end of a bell crank lever or shaft ll, one end of which has an eccentric or cam portion II which is adapted to coact with an insulating wearing surface or abutment. carried by the movable end of the thermostatic switch arm 40. The end 01' the crank shaft Ii is pivotally supported in the switch housing. The switch housing is secured in the casing II in a suitable manner as for instance by means of a bolt and nut BI.

One wall of thecasing II is notched at it to allow tor the movement of the float lever ii so that the switch unit and the attached float ll may be removed without disturbing the other parts or the casing II and its contents.

Under normal conditions the switch is actuated in the manner of a quick make and break,

switch by the movement of the float 50 when it rises and falls in the main liquid'reservoir chamber II. This float in a standard type mechanism starts and stops the motor when approximately one hall pint of fuel is used and under normal operating conditions it requires from one to two minutes, depending upon the lift 01 the oil, to pump this one-halt pint.

Under abnormal conditions, for instance, when a pipe line is broken or in case the float ll fills, or in case the tank runs dry, the motor would tend to run continuously because there could be no action of the float I0 to shut oil the pump motor.

The thermostatic action of the arm 40, however, is so designed that after a period of approximately five minutes the heat of the motor enclosed within the casing is will operate the thermostat and open the circuit of the switch even though the float 50 remains down. This thermostat may be reset automatically or by hand. In the latter case a reset button of conventional type may be employed to extend outside or through the cover and arranged to indicate when the switch is on or 08.

Safety precautions as above indicated are of the greatest importance in a construction of this character since the continued flow oi iuel oil or overflow of the oil is likely to create a dangerous fire hazard. Since the continued successi'ul operation of the fuel supply is of vital importance to the person relying upon it, it is essential for commercial purposes that the parts of the motor and pump which are likely to be deranged be readily inspected and replaceable so as not to interrupt the continuous operation or the system.

The invention herein described and claimed has been proven to efl'ectively supply the demand for such apparatus.

The enclosure I! for the motor and delay action thermal means, not only safeguards these parts against coming in contact with the liquid but also localizes the heating of the motor and prevents its ventilation in as free a manner as might otherwise occur were it not for this enclosure I! which impedes convection currents of fluid, especially air, around the motor and thermostat. It will be seen that the chamber supplied by the pump not only has a normal discharge passage into the constant level chamber located above the bottom of the first chamber, but both the pump chamber and the constant level chamber have overflow outlets into the overflow chamber is where any overflow fuel is returned to the storage tank from which it is drawn by the pump.

I claim:

1. The combination with a tank, oi means for supplying liquid thereto, mechanism for controlling said means in response to the liquid level in said tank, a substantially constant level tank formed by a partition in the flrst tank, said constant level tank having sides located above the bottom 01' said first tank and said constant level tank being supplied from the first mentioned tank, overflow outlets from each tank, said means including a supply reservoir for the first tank with a pipe therebetween, and a pipe connecting said overflow outlets with said reservoir.

2. The combination with a tank, of means for supplying liquid thereto, mechanism ior controlling said means in response to the liquid level in said tank, a substantially constant level tank formed by a partition in the first tank, with the sides or said constant level tank located above the bottom of said first tank and said constant level tank being supplied from the flrst mentioned tank, overflow outlets from each tank, a supply reservoir and a pipe connecting the same with the first tank, a pipe connecting said overflow outlets with said supply reservoir, a valve controlling the flow of liquid from the flrst tank into the second in response to the liquid level in the second tank, and a filter between said valve and the first tank, said filter being replaceable as. a unit and being held by said partition between said flrst and second tanks.

3. A liquid supply tank having partitions dividing it into a main supply chamber, a constant level chamber and an overflow chamber, with overflow outlets from the main supply chamher and the constant level chamber to the overflow chamber, means for supplying liquid to the main supply chamber, means responsive to the level or the liquid in the main supply chamber for controlling the means for supplying liquid to the main supply chamber, one of the partitions having a passage from the main supply chamber to the constant level chamber, means responsive to the level oi! liquid in the constant level cham her for controlling the normal passage of liquid from the main supply chamber to the constant level chamber and a discharge pipe leading from the overflow chamber.

, HERMAN J. HAMMERLY. 

